1. Field of the Invention
The present invention relates to weight measurement devices, for example, weighing scales.
2. Related Art
In a conventional weighing scale, there may be a chamber defined by a base and a platform on which a subject stands, and one or more load cells are contained in the chamber as disclosed in JP 2003-307454-A and JP 2004-156937-A. The load cell generates an electric signal due to the weight exerted on the platform. On the basis of the electric signal, the amount of weight on the platform is calculated.
The load cell incorporates a flexure element having a fulcrum point supported with respect to the base and a force point (application point of the force) coupled to the platform. When a load is applied to the force point from the platform, the part of the flexure element between the force point and the fulcrum point deforms, and the degree of deformation is measured with a suitable element, for example, a strain gauge.
In the technique described in JP 2003-307454-A, an elastic member is interposed between the platform and the flexure element. This elastic member maintains the connection between the platform and the flexure element, and allows the platform to change its position with respect to the flexure element. However, in order to secure a sufficient deformation, the elastic member must have a considerable thickness. This results in enlargement of the entire thickness of the weight measurement device, such as a weighing scale. In particular, if the elastic member is made of rubber, it is necessary to increase the thickness since the rubber will harden.
Accordingly, the present invention provides a weight measurement device in which the thickness can be reduced significantly.